It is proposed to continue our work in the isolation and characterization of the immunologically active component(s) of "Transfer Factor". Donors who are highly sensitive to a variety of fungal or tumor antigens will be employed as sources of "Transfer Factor". The components of Transfer Factor will be separated by a combination of gel filtration, isoelectric focusing and thin layer chromatography. Assays will be carried out in vivo and attempts will be made to develop a suitable in vitro system for assay. We will also be studying the possibility of using primates as animal models for the assay of "Transfer Factor".